SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3e974322f092e6c67ef00eefab00036343353f8ef293a6643cda518d0b58db9f' 
  AND token = 'X9eYQ+ESAQXvbnMfgvK5FZXqikmnT0nmFci9TP1m/Ew=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}